"As a nation, we honour his service and mourn his passing," Prime Minister Stephen Harper said Thursday in a statement. "The passing of Mr. Babcock marks the end of an era."

More than 650,000 Canadians and Newfoundlanders served during World War I, according to Jean-Pierre Blackburn, minister of veterans affairs and minister of state (agriculture).

With Babcock's passing, there is no one "to tell us first-hand about this defining time" in history, Blackburn said in a statement.

Babcock, who immigrated to the U.S. in the early 1920s, was modest about his fame as Canada's last surviving World War I vet.

Having never made it to the front lines, he viewed himself as "just a tin soldier."

Still in Canada when the military discovered his true age, Babcock later said he was one of several dozen young soldiers sent to Europe as reserves for the Royal Canadian Regiment.

After he was assigned to the 26th Reserve Battalion in England, he and 1,300 Canadian soldiers under age 19 were placed in the Young Soldiers Battalion.

"If the war had lasted another year, I would have fought," Babcock told the Canadian Press in 2007.

Babcock was born July 23, 1900, and grew up on a farm in Kingston, Ontario.

After moving to the U.S., he served in the Army from 1921 to 1924 and married his first wife, Elsie, who died of cancer in 1976. His second wife, Dorothy, was a nurse who had helped care for his first wife.

Babcock owned a heating, plumbing and air-conditioning business for more than 25 years before becoming an estimator for a mechanical contractor. For that job, he received a pilot's license at 65 to fly to remote job sites.

He retired at 89.

During World War II, Babcock once again tried to see battle, but the military turned him down -- he was too old.

Bob Johnson, a retired Air Force lieutenant colonel who helps World War I and II veterans receive recognition, said Babcock "represents a generation that would give their lives for their country to preserve their way of life."

Johnson first met Babcock in 2004 at his Spokane home and returned in July when Babcock was "two days shy of 109."

"I was amazed at his mental sharpness," said Johnson. "He made me laugh, he recited limericks, sang songs and recited the alphabet backward. He also liked to spell out his name in Morse code."

The United States has one surviving World War I veteran, Frank Woodruff Buckles of West Virginia, who recently turned 109.

In addition to his wife, Babcock is survived by his children, John Babcock Jr. and Sandra Strong; stepsons Eric and Mark Farden; 16 grandchildren; and nine great-grandchildren.